Tilting device for hospital beds



'H- E RD TILTING DEVIGE' 10R- HpsPmAL sans Filed mg .23. 1921 IS-Sheets-Shee' Dem- 4 1,517,418

a H. FORD TILTING DEVICE FOR HOSPITAL BEDS File d July 23 I92] 3 shets -sheet 2 Dec. 1924- 1,517,418

. H. FORD .IILTING DEVICE FOR HOSPITAL BEDS Filed July 23. 1921 ssneetsr-sh eet 5 atented Dec. 2, 1924.

HENRY soap, or nEAnBonN, nmme aa.

TILTING DEVICE non HOSPITAL BEDS.

Application filed J'u1y 23, 1921. SeriaI'No 486,956.

To all wiiom it may concern:

Be it known that I, HENRY Form, a citizen of the United-States of America, residing at Dearborn, in the county of Wayne and State of Michigan, have invented certain newiand useful Improvements in Tilting Devices for Hospital Beds, of which the following is a-specification, reference being had therein to the accompanying drawings.

This invention relates to invalid beds and has special reference to an adjustable framework for hospital beds by which an invalid or patient may be placed in a sitting or reclining position on a bed or like structure.

The primary object of my invention is to furnish a bed with an adjustable framework including back and leg supports that may be placed at an inclination relative to the :bed to safely support a patient in a lounging or reclining posture relative to the bed, and provision is made for adjusting the body and leg supports while being occupied.

Another object of the invention is to provide a lounging attachment for a bed which may be adjusted by the occupant of the bed.

A further object of this invention is to provide a bed attachment having adjustable body and leg supports and positive and reliable means, in a manner as hereinafter set forth, for independently adjusting said supports, said means including a novel reduction gear which serves the purpose of a lock for preventing collapse or accidental movement of the body and leg supports after being adjusted.

A still further object of this invention is to provide a tiltable attachment for hospital beds wherein the'parts are constructed so as to be applicable to an ordinary iron bed or cot, easy to install and adjust, and highly efficient as a comfortable support for apatient or invalid.

The above are a few of the objects obtained by th construction to be hereinafter described and then claimed, and reference will now be had to the drawings, wherein- Figure 1 is a side elevation of a bed provided with. the attachment, showing the back and leg supports in raised positions by dot and dash lines;

Fig. 2 is a horizontal sectional view of the bed, taken on the line III-I- of Fig. 1, and looking. in the direction of the arrows;

Fig. 3 is an enlarged cross sectional view of a portion .of the bed, ta'ken'on the line --IIIIII of Fig. 1, and i'llustrating one of 1 and 2'denote head'and foot pieces connected by side rails 3, said rails 'and'the head and foot pieces constituting a bed or cot structure.

Attached to the side rails 3, intermediate the ends thereof and preferably by angle brackets 4, are stationary meinbers 5. l-iingedly or otherwise connected to the ends of the stationary members 5 are the side rails 6 of a back support 7 and the side' rails 8 ofa foldable leg support 9. Hinges 10 may be conveniently used for connecting the rails 6 and 8 to the. stationary members 5 so that said rails will abut the ends of said members when. in a horizontal plane on the bed rails 3. The hinges 10 also permit of the supports 7 and 9 being raised or tilted at an acute or obtuse angle relative to the bed rails, and the siderails 8 of the leg support are each made of two sections hingedly connected together, as at 11, so; that the leg support may be broken upwardly to permit of the thighs being/supported at other angles than the legs, thus permitting a patient placing the lower extremities of the body in a comfortable position, to brace thebody against the support. 7. The leg support therefore includes a thigh section and a foot section, and contributing to an easy movement or adj ustmentof the leg support 9 are antifrictional rollers 12 carried by the foot section and bearing on the side rails 3 of the lOQClJ.

Suitably secured to the side rails3, intermediate the ends thereof, are depending cylindrical housings 13' having outer end walls 14 in which are journaled hubs 15 of hand wheels 16. On the side of each housing 13 is a bearing 17,.and by reference to Fig.2,- it will be noted that the housings 13 are not in opposed relation, but are reversely arranged or positioned so that the bearing 17 of each housing will transversely aline with the hub 15 of the opposite housing. This is for the purpose of permitting of independent shafts 18 being used and. said shafts independently adjusted from the independent housings, there being a hand wheel 16 at each side of the bed structure. Each shaft is tubular with one end thereof journaled in the bearing 17 and closed by a cap 19. The opposite end of the shaft is loose on the end of a stub shaft 20 extending axially of the housing 13 and loose in the hub 15 thereof, said stub shaft assisting in supporting the hand wheel 16.

The hub 15 has an eccentric portion 21 on which is fitted or mounted a compound pinion 22, said pinion having one set of teeth 23, preferably twenty-one in number, mesh ing with an internal rack 24 of the housing 13, and another set of teeth 25, preferably twenty in number, meshing with an internal gear 26 having a hub portion 27 loose on the stub shaft 20. The hub portion 27 of the gear 26 is journaled in a bearing 28 of a cap or closure plate 29 detachably mounted in the inner end of the housing 18, and said cap or closure plate may be adjusted to hold the internal gear 26 and the compound pinion 22 in proper relation, besides providing an end abutment against any end thrust during the operation of the gearing. A driving relation is established between the end of the shaft 18 and the hub portion 27 of the internal gear 26 by tongues 30 on the ends of the shaft 18 extending into notches 81 in the ends of the hub 27.

The operative connection between wheel 16 and shaft 18, just described not only provides for gear reduction activity but serves to prevent shaft rotation except by operation of the wheel. This will be understood from the following brief description of the gearing in operation:

Since gear 22 is mounted on the eccentric hub 15, it will be understood that the gear axis is not alined with the axis of stub shaft 20 and the opening of housing 18, these latter fixing the axis of rotation of the wheel. Hence, rotation of the wheel causes its hub to carry the axis of gear 22 in a circular path the diameter of which, of course, depends upon the eccentricity of hub 15. As the teeth 21 of the housing are fixedly positioned and do not change position, it will be readily understood that this motion of the gear axis in its circular path causes the gear teeth 23 to successively engage the teeth 2 1, setting up the characteristics of a rolling action of gear 22 on the toothed face of the housing. This movement of gear 22, obviously, causes teeth 25 to be brought successively in contact by a similar rolling action on the teeth of internal gear 26, the latter being capable of movement on the axis of shaft 18. The variation in number of teeth in the two tooth faces of gear 22 sets up the condition of an advance of the internal gear an angular distance equal to the angular dimensions of a tooth during each complete rotation of wheel 16; the angular displacement of internal gear 26 would be approximately 18 for each rotation of wheel 16. This, of course, depends upon the tooth ratio employed.

This slow-motion effect, producing the ability to move a heavy load by the application of a relatively small amount of power, is made possible by the fact that the axis of gear 22 travels in an orbital or circular path when the wheel is turned in either direction; if the axis of, the gear is unchanged, the gearing is locked against movement in either direction. This latter will be understood from the fact that, assuming a turning movement be attempted by load application on hub 27, the tendency would be to apply advancing pressure on the tooth 25 of gear 22 which is in engagement with the tooth of internal gear 26, with gear 22 revolving about the hub 15 by a sliding action; such movement of gear 22 cannot be had, however, since the tooth 28 that is in engagement with tooth 24 of the housing would be required to advance as well, and such advance is prevented by the inability of the tooth 24 to change position.

In other words, movement of the internal gear 26 can take place only when the axis of gear 22 has a movement in an orbital patha movement possible only through change in position of hub 15; movement of gear 22 on its own axis independent of wheel movement is prevented by the engaging teeth 23 and 2 1. Hence, all movement of shaft 18 is wholly dependent on movement of the wheel 16, the shaft being maintained immovable in the position to which it has been brought by wheel movement until the wheel is again actuated, the wheel being at all times free to be moved Without any preliminary manipulation of any structure, the wheel being permanently free from all restraint against movement, the locking action being provided within the gear structure and the inability of the latter to force rotation of the wheel hub.

Pinned or otherwise fixed on the ends of each of the tubular shafts 18 are the inner sleeve ends 32 of long cranks 33, said cranks having the outer ends thereof connected to the body and leg supports by links 34. The cranks of one of the shafts are connected to the body support 7 and the cranks at the other shaft to the thigh section of the leg support 9, and these supports may be inclependently adjusted at opposite sides of the bed structure. It will be noted that the reduction gear mechanism is adjacent the stationary members 5 and should a patient be physically able it is possible for the patient to lean over either edge of the bed and adjust either support.

Each gear reduction mechanism has its gears of such ratio that the shaft controlled by such mechanism will be rotated at a comparatively low speed by the hand Wheel at the end of said shaft. Furthermore, the arrangement of the internal rack, the internal gear, and the compound gear of each mechanism is such that the rack and gears constitute a lock for preventing accidental rotation of the shaft due to any weight on or against the support controlled by the shaft.

This is due, of course, to the fact that the connection between the support and shaft 18 causes the connecting means to move with the shaft, and, due to the coupled relation between shaft 18 and the hub 27 of the internal gear 26, any load that may be applied by the weight on the support would be attempting to move gear 22 wholly on its own axis, a movement that is impossible because of the locking action set up by the engagement of teeth 23 and 24: as heretofore pointed out.

Hence, it will be understood that because of the slow-motion action of the gearing, it will be possible for the occupant of the bed, without the exertion of any material force, to efiect tilting action in a raising or lowering direction by simply turning the wheel 16, the support remaining held against movement, accidental or otherwise, as long as the wheel remains stationary, there being no requirement of manipulating any locking device preliminary to movement, the locking action being within the gearing itself with the gearing entirely free to be moved without preliminary manipulation.

The construction is not only one which is simple and efficient and capable of operation by the occupant of the bed withoutrequiring movement from position, but provides the additional and important advantages of having the operating parts entirely enclosed or housed so as to avoid the possibility of dust collection or moisture conditions affecting the operating mechanism such as to render it more difiicult to operate. And, being housed, it is obvious that lubrication can be had without itself becoming a dust-collecting agency, since the gearing and operating parts are enclosed in a dust-proof housing or casing. 1

As arms 33 are practically parts of the shaft 18, the sweep of the pivot point between an arm and its link 34 is that of an angular distance equal to that of the increment of angular movement of shaft 18 provided by the wheel manipulation, the length of the arm determining the actual distance included within the increment of the sweep movement.

susceptible to such variations and modifications as fall within the scope of the appended claims.

What I claim is 1. In invalid bed constructions wherein a support is tiltable by the patient to shift its angularity to the vertical, mechanism operative by the patient for positioning the support within the range of the tilting movement, said mechanism including a shaft rotatable on its axis and operatively connected to the support at spaced points in the width of the bed to provide positioning movements of the shaft, a rotatable manipulating element positioned accessible to the patient, and means operatively connecting the element and shaft and operative to shift the position of the support by element move ment and to maintain the shaft against movement in the absence of element movement, said means including a gearing assembly having one of its gear members mounted on the element and movable thereby to shift the axis of such gear member in an orbital path, an internally-toothed gear co-operating with and rotatable by said gear member and operatively connected with said shaft to move therewith, and a fixed toothed face co-operative with the gear member to prevent movement of said gear member on its own axis in the absence of element movement.

2. Mechanism as in claim 1 characterized in that the element is formed with a hub portion with the hub portion having a seat co-operative with a casing portion and a second seat for the gear member, the casing 100 seat being axially alined with the shaft axis, the gear member seat being eccentric relative to the casing seat.

3. Mechanism as in claim 1 characterized in that the fixed tooth face is carried by a 1 casing member with the axis of such tooth face alined with the axis of the internallytoothed member, the gear member having a pair of axially-alined tooth faces co-operating respectively with the teeth of the cas- 110 ing and internally-toothed member, the axis of the gear member faces being out of alinement with the axis of the casing and internally-toothed members.

4. Mechanism as in claim 1 characterized 115 in that the gearing assembly is mounted within a casing or housing within the walls of which the element and internally-toothed member are journalled in axial alinement.

In testimony whereof I aflix my signature 120 in presence of two witnesses.

HENRY FORD.

Witnesses:

E. G. SmBoLn, J. EMMET HALL. 

